Yahoo ranking down?

what is the reason of down ranking?

[mahav]

i have do seo (optimisation)work for my sites but i saw after some month which keywords rank at google, are not rank at yahoo, and which keywords rank at yahoo are not rank at google what is the reason?

[cnvi]

There is no way that I know of to pin a specific reason for a change in rankings. If we had that answer we would all be quite rich. You can speculate all day but unless you own a 100% accurate crystal ball, there is no perfect answer to your question.

And many times its not necessarily your rankings going down - but your competition's rankings going up.

Rankings go up and down all the time. The best way to keep them from going down is to follow published search engine guidelines, obtain relevant links, and keep your content always updated. You don't want your website to have cobwebs on it or be perceived as becoming stale.

[Robert Charlton]

mahav - Take a look at these two recent discussions, which may have a bearing on your problems. I think you'll see that there are many others in a similar situation... doing well in Google but not doing well in Yahoo, and not quite understanding what factors Yahoo considers important....

Can't Figure Yahoo out.
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Weather Report: Yahoo! Search Index Update May 27, 2008
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